I can't say for certain as I've never used XP (or allowed html5 video), but this seems to say firefox supports html5 on xp:
https://en.wikipedia.org/wiki/HTML5_video
@InHeavenThereIsNoBeer Technically, any browser can support html5, providing the 'new' stuff is set inside a block... and within that block, a suitable redirect could be defined to handle just about anything... It's just script after all.
But in practice, no. That an author
could make a page compatible with any browser, doesn't mean he will.
This issue is exactly what drove me off of XP about year ago. My last xp box, an Asus eeePC netbook, was almost literally rendered useless on the web... It had been my PIM for nigh on a decade, but antiquated browser, with antiquated flash and java, made for a very limited ability online. Not so bad that the bouncy-jangly bits don't work, but fairly often a page would choke the browser, which would choke xp, and cause a need for a hard shutdown and reboot. very unhappy.
That's why that little netbook went to Linux.